Core suspension system for swimming pool type reactor



March 7, 1967 TADASHI AlZU ETAL 3,

CORE SUSPENSION SYSTEM FOR SWIMMING POOL TYPE REACTOR Filed A ril 15,1964 2 Sheets-Sheet 1 INUEHTO% dash'a Qiau Kiqom': Hiru ATTORNEYS March7, 1967 TADASHI AlZU ETAL 3,308,030

coma SUSPENSION SYSTEM FOR SWIMMING POOL TYPE REACTOR Filed April 15,1964 2 Sheets-Sheet 2 J *Dfrecfian ofmovemenf Urea/7'00 0f movemenfInuEnToRs Tsdaskn fi au Kiwom'l Kin u ATTORNEY United States Patent3,308,030 CORE SUSPENSION SYSTEM FOR SWIMMING POOL TYPE REACTOR TadashiAizu and Kiyomi Kiryu, Hitachi-shi, Japan, as-

signors to Hitachi, Ltd., Tokyo, Japan, a corporation of Japan FiledApr. 15, 1964, Ser. No. 359,982 Claims priority, application Japan, Apr.16, 1963, 38/ 18,191 2 Claims. (Cl. 176-27) This invention relates to aswimming pool type reactor.

As an experimental reactor, a swimming pool type reactor with its coresubmerged in considerably deep water is used, generally, due to itsconvenience for experiments and its simplicity in operation. For thisswimming-pool reactor, there are two types of the device; one of whichis provided with various experimental arrangements in the wall or thepool of the reactor with a centrally disposed fixed core, and the otheris provided with a bridge stretched over the pool, the core beingmovable by fixing the core to the bridge and by moving the bridge. Sincethese reactors have been constructed in rectangular shape, theirconstruction and the experimental space are considerably restricted sothat their use has been inconvenient and also uneconomical.

Accordingly, it is an object of the present invention to provide aswimming pool type reactor with a relatively small pool capable ofperforming various experiments more effectively than the conventionallarge pool type reactor and also capable of performing the experimentaloperations easily and safely. This is accomplished by making the corefreely movable in the pool by forming the swimming pool type reactorcircularly and providing a supporting frame movable on a rotatablebridge so that the dead space'in the pool is eliminated relative to theconventional swimming pool type reactor.

According to the present invention, there is provided a swimming pooltype reactor characterized which that it comprises a circular poolsurrounded by a cylindrical side wall constructed to shield againstradiation. The inside of said side wall is filled with water and alsoprovided with a core. A plurality of experimental bores are providedthrough said side wall of the pool and these are adapted to be insertedwith test material for experimentals. A rail is circularly disposed onthe top end surface of said pool along its circumference. A bridgehaving wheels mounted on its opposite ends is stretched over this pooland adapted to run along the rail. A carriage is constructed to run onthis bridge. The core is adapted to be brought into any position beforethe experimental bores in which irradiation is desired by suspendingsaid core from said carriage.

The technical construction of the invention suitable to fulfill theseobjects will be understood from the following description of anembodiment according to the present invention taken together with theaccompanying drawings in which;

FIG. 1 shows a longitudinal section of a reactor illustrating anembodiment according to the present invention, and

FIG. 2 shows a plan view of the reactor shown in FIG. 1.

Referring now to the drawings, and particularly to FIG. 1 thereof, anillustrative embodiment of this invention is seen to comprise abiological shield 1 formed in circular ICC shape, the interior wall ofthe shield being provided with lining 2. On the top surface of thecircular formed biological shield there is provided a circumferentialrail 8 on which the bridge 7 is carried to extend it over the reactor.

The core 4, which is covered with a reflector 5, is submerged in coolingwater 3 in the pool and is suspended by means of a supporting frame 6.

The biological shield 1 is provided with several experimental bores 9therein in circumferential positions of the member. The core 4 may becapable of running linearly on the bridge 7 so that it can be presentedto an experimental bore 9 as desired, or the core 4 may be disposed in aposition in which the center of the core 4 is aligned with the center ofthe experimental bore 9. The supporting frame 6 may be fixed to thebridge 7 so that the core 4 is disposed in a position adjacent the beamtube 9. In all cases the effects are the same.

Beam tubes 9 are disposed radially around the circumference of thereactor, and when an experiment is performed with beam tube 9, thebridge 7 is rotated so that the center of the core 4 is aligned with thecenter of the beam tube 9. After the alignment is confirmed, thesupporting frame 6 is moved horizontally until the reflector 5 contactswith the interior surface of the lining 2, and then the supporting frame6 is fixed there. Thereafter, the operation of the reactor is initiated.When reactor core 4 is against a side wall, and only a few of beam tubes9 are being irradiated, the remaining space in the pool and the unusedbeam tubes 9 may be utilized in many Ways. For example, as shown inFIGURE 1, test body 10 may be placed in the pool and other experimentsperformed using the nonirradiated beam tubes. This is possible sincethese tubes are separated from core 4 and shielded by the water in thepool.

When it is desired to use several beam tubes 9 simultaneously, any beamtube 9 can be connected to the core 4 by providing a movable beam tubeof small neutron loss.

Thus, with radially arranged beam tube 9, the space for one of the beamtubes may be made sufficiently large, and the mounting of theexperimental device and the shielding member and the experimentaloperations are made very easily. When a large shielding experiment isperformed, the shielding body may be disposed in the circular pool andthe instrument tube in the biological shield utilized, or a measuringpool may be provided such as shown by the double dot and dashed line inFIG. 2.

What is claimed is:

1. In a pool-type reactor, the combination, comprising:

a circular pool having sidewalls, forming a radiation shield, and abottom, constructed to retain a cooling agent,

guide means disposed around the upper periphery of said sidewalls,

bridge means movably mounted on said guide means for rotational movementaround the periphery of said pool,

carriage means mounted for movement along said bridge means,

reactor core means suspended from said carriage means into said pool,

irradiation station means disposed along the sidewalls ofdsaid pool forcontaining experimental samples, an

control means for selectively positioning said bridge by the combinedrotational motion of said bridge means and translational motion of saidcarriage means.

References Cited by the Examiner UNITED STATES PATENTS 2,992,176 7/1961Schoessow 17662 X 3,006,834 10/1961 Loeb 176-62 X 3,042,601 7/1962 Loeb176-62 X CARL D. QUARFORTH, Primary Examiner.

L. DEWAYNE RUTLEDGE, Examiner.

2. IN A CIRCULAR POOL-TYPE REACTOR, THE SUBCOMBINATION, COMPRISING;BRIDGE MEANS MOUNTED TO BE ROTATED ABOUT THE UPPER PERIPHERY OF SAIDPOOL, CARRIAGE MEANS MOUNTED ON SAID BRIDGE MEANS TO MOVE ALONG SAIDBRIDGE MEANS, SAID CARRIAGE MEANS INCLUDING REACTOR CORE MEANS SUSPENDEDTHEREFROM INTO SAID POOL, CONTROL MEANS FOR INDEPENDENTLY ACTIVATING ANDMOVING SAID BRIDGE MEANS AND SAID CARRIAGE MEANS TO LOCATE SAID REACTORCORE IN ANY POSITION WITHIN THE POOL BY THE COMBINED ROTATIONAL MOTIONOF SAID BRIDGE MEANS AND TRANSLATIONAL MOTION OF SAID CARRIAGE MEANS.